The vehicle is equipped with electronic multiport fuel injection that is supplied by a new electronic returnless fuel system. The powertrain control module (PCM) receives pressure information from a fuel pressure sensor mounted on the fuel injection rail. The PCM is able to maintain constant fuel pressure by varying the fuel pump module output.
This is accomplished by increasing or decreasing voltage supplied to the fuel pump module. The returnless fuel system offers improved economy, lower fuel temperatures and decreased fuel vapor in the fuel tank.
The fuel system contains the following main components
- Fuel filter
- Fuel pump module
- Inertia fuel shutoff switch
- Fuel tube grounding clip
- Fuel filler tube
- Fuel tank
SPECIAL TOOLS REFERENCE Vehicle Communication Module (VCM) and Integrated Diagnostic System (IDS) software with appropriate hardware, or equivalent scan tool
Principles of Operation
Note. The following procedure diagnoses a slow to fill concern only. For all other concerns, refer to the INTRODUCTION - GASOLINE .
The fuel tank filler pipe assembly is used to refuel the vehicle. The fuel tank filler pipe flapper valve prevents spitback of fuel during and after refueling. The fuel tank stores the fuel. The fuel tank contains a fuel pump (FP) module. The FP module consists of a fuel level sensor and a FP. The fuel level sensor sends a signal to the fuel gauge informing the driver of how much fuel is in the fuel tank. The FP provides fuel to the fuel tubes which supply the fuel rail.
During refueling, the fuel tank vents to the atmosphere through the vent and filler pipes, on vehicles without on-board refueling vapor recovery (ORVR) systems. In vehicles equipped with ORVR the fuel tank and filler pipe are designed so that when the vehicle is being refueled, fuel vapors in the fuel tank travel to the evaporative emission (EVAP) canister, which absorbs the fuel vapors and vents the pressure from the fuel tank during refueling.
Normal Operation
Under normal operation, fuel should flow at a steady rate through the fuel tank filler pipe into the fuel tank. As fuel enters the fuel tank air is vented through the filler pipe or the on-board refueling vapor recovery (ORVR) system.